drm/msm/dsi: drop multiple pll enable_seq support

The only PLL using multiple enable sequences is the 28nm PLL, which just
does the single step in the loop. Push that support back into the PLL
code.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org>
Tested-by: Stephen Boyd <swboyd@chromium.org> # on sc7180 lazor
Link: https://lore.kernel.org/r/20210331105735.3690009-6-dmitry.baryshkov@linaro.org
Signed-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/dsi/phy/dsi_phy_14nm.c

@@ -1087,8 +1087,7 @@ struct msm_dsi_pll *msm_dsi_pll_14nm_init(struct platform_device *pdev, int id)
 
 	pll_14nm->vco_delay = 1;
 
-	pll->en_seq_cnt = 1;
-	pll->enable_seqs[0] = dsi_pll_14nm_enable_seq;
+	pll->enable_seq = dsi_pll_14nm_enable_seq;
 
 	ret = pll_14nm_register(pll_14nm);
 	if (ret) {

drivers/gpu/drm/msm/dsi/phy/dsi_phy_28nm.c

@@ -311,7 +311,7 @@ static const struct clk_ops clk_ops_dsi_pll_28nm_vco = {
 /*
  * PLL Callbacks
  */
-static int dsi_pll_28nm_enable_seq_hpm(struct msm_dsi_pll *pll)
+static int _dsi_pll_28nm_enable_seq_hpm(struct msm_dsi_pll *pll)
 {
 	struct dsi_pll_28nm *pll_28nm = to_pll_28nm(pll);
 	struct device *dev = &pll_28nm->pdev->dev;
@@ -386,6 +386,19 @@ static int dsi_pll_28nm_enable_seq_hpm(struct msm_dsi_pll *pll)
 	return locked ? 0 : -EINVAL;
 }
 
+static int dsi_pll_28nm_enable_seq_hpm(struct msm_dsi_pll *pll)
+{
+	int i, ret;
+
+	for (i = 0; i < 3; i++) {
+		ret = _dsi_pll_28nm_enable_seq_hpm(pll);
+		if (!ret)
+			return 0;
+	}
+
+	return ret;
+}
+
 static int dsi_pll_28nm_enable_seq_lp(struct msm_dsi_pll *pll)
 {
 	struct dsi_pll_28nm *pll_28nm = to_pll_28nm(pll);
@@ -619,15 +632,11 @@ struct msm_dsi_pll *msm_dsi_pll_28nm_init(struct platform_device *pdev,
 	if (type == MSM_DSI_PHY_28NM_HPM) {
 		pll_28nm->vco_delay = 1;
 
-		pll->en_seq_cnt = 3;
-		pll->enable_seqs[0] = dsi_pll_28nm_enable_seq_hpm;
-		pll->enable_seqs[1] = dsi_pll_28nm_enable_seq_hpm;
-		pll->enable_seqs[2] = dsi_pll_28nm_enable_seq_hpm;
+		pll->enable_seq = dsi_pll_28nm_enable_seq_hpm;
 	} else if (type == MSM_DSI_PHY_28NM_LP) {
 		pll_28nm->vco_delay = 1000;
 
-		pll->en_seq_cnt = 1;
-		pll->enable_seqs[0] = dsi_pll_28nm_enable_seq_lp;
+		pll->enable_seq = dsi_pll_28nm_enable_seq_lp;
 	} else {
 		DRM_DEV_ERROR(&pdev->dev, "phy type (%d) is not 28nm\n", type);
 		return ERR_PTR(-EINVAL);

drivers/gpu/drm/msm/dsi/phy/dsi_phy_28nm_8960.c

@@ -515,8 +515,7 @@ struct msm_dsi_pll *msm_dsi_pll_28nm_8960_init(struct platform_device *pdev,
 	pll->save_state = dsi_pll_28nm_save_state;
 	pll->restore_state = dsi_pll_28nm_restore_state;
 
-	pll->en_seq_cnt = 1;
-	pll->enable_seqs[0] = dsi_pll_28nm_enable_seq;
+	pll->enable_seq = dsi_pll_28nm_enable_seq;
 
 	ret = pll_28nm_register(pll_28nm);
 	if (ret) {

drivers/gpu/drm/msm/dsi/phy/dsi_pll.c

@@ -5,46 +5,6 @@
 
 #include "dsi_pll.h"
 
-static int dsi_pll_enable(struct msm_dsi_pll *pll)
-{
-	int i, ret = 0;
-
-	/*
-	 * Certain PLLs do not allow VCO rate update when it is on.
-	 * Keep track of their status to turn on/off after set rate success.
-	 */
-	if (unlikely(pll->pll_on))
-		return 0;
-
-	/* Try all enable sequences until one succeeds */
-	for (i = 0; i < pll->en_seq_cnt; i++) {
-		ret = pll->enable_seqs[i](pll);
-		DBG("DSI PLL %s after sequence #%d",
-			ret ? "unlocked" : "locked", i + 1);
-		if (!ret)
-			break;
-	}
-
-	if (ret) {
-		DRM_ERROR("DSI PLL failed to lock\n");
-		return ret;
-	}
-
-	pll->pll_on = true;
-
-	return 0;
-}
-
-static void dsi_pll_disable(struct msm_dsi_pll *pll)
-{
-	if (unlikely(!pll->pll_on))
-		return;
-
-	pll->disable_seq(pll);
-
-	pll->pll_on = false;
-}
-
 /*
  * DSI PLL Helper functions
  */
@@ -64,15 +24,36 @@ long msm_dsi_pll_helper_clk_round_rate(struct clk_hw *hw,
 int msm_dsi_pll_helper_clk_prepare(struct clk_hw *hw)
 {
 	struct msm_dsi_pll *pll = hw_clk_to_pll(hw);
+	int ret = 0;
 
-	return dsi_pll_enable(pll);
+	/*
+	 * Certain PLLs do not allow VCO rate update when it is on.
+	 * Keep track of their status to turn on/off after set rate success.
+	 */
+	if (unlikely(pll->pll_on))
+		return 0;
+
+	ret = pll->enable_seq(pll);
+	if (ret) {
+		DRM_ERROR("DSI PLL failed to lock\n");
+		return ret;
+	}
+
+	pll->pll_on = true;
+
+	return 0;
 }
 
 void msm_dsi_pll_helper_clk_unprepare(struct clk_hw *hw)
 {
 	struct msm_dsi_pll *pll = hw_clk_to_pll(hw);
 
-	dsi_pll_disable(pll);
+	if (unlikely(!pll->pll_on))
+		return;
+
+	pll->disable_seq(pll);
+
+	pll->pll_on = false;
 }
 
 void msm_dsi_pll_helper_unregister_clks(struct platform_device *pdev,

drivers/gpu/drm/msm/dsi/phy/dsi_pll.h

@@ -12,7 +12,6 @@
 #include "dsi.h"
 
 #define NUM_DSI_CLOCKS_MAX	6
-#define MAX_DSI_PLL_EN_SEQS	10
 
 struct msm_dsi_pll {
 	enum msm_dsi_phy_type type;
@@ -23,9 +22,8 @@ struct msm_dsi_pll {
 
 	unsigned long	min_rate;
 	unsigned long	max_rate;
-	u32		en_seq_cnt;
 
-	int (*enable_seqs[MAX_DSI_PLL_EN_SEQS])(struct msm_dsi_pll *pll);
+	int (*enable_seq)(struct msm_dsi_pll *pll);
 	void (*disable_seq)(struct msm_dsi_pll *pll);
 	int (*get_provider)(struct msm_dsi_pll *pll,
 			struct clk **byte_clk_provider,